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Unlike the electroweak sector of the standard model of particle physics, quantum chromodynamics (QCD) is surprisingly symmetric under time reversal. As there is no obvious reason for QCD being so symmetric, this phenomenon poses a theoretical problem, often referred to as the strong CP problem. The most attractive solution for this requires the existence of a new particle, the axion-a promising dark-matter candidate. Here we determine the axion mass using lattice QCD, assuming that these particles are the dominant component of dark matter. The key quantities of the calculation are the equation of state of the Universe and the temperature dependence of the topological susceptibility of QCD, a quantity that is notoriously difficult to calculate, especially in the most relevant high-temperature region (up to several gigaelectronvolts). But by splitting the vacuum into different sectors and re-defining the fermionic determinants, its controlled calculation becomes feasible. Thus, our twofold prediction helps most cosmological calculations to describe the evolution of the early Universe by using the equation of state, and may be decisive for guiding experiments looking for dark-matter axions. In the next couple of years, it should be possible to confirm or rule out post-inflation axions experimentally, depending on whether the axion mass is found to be as predicted here. Alternatively, in a pre-inflation scenario, our calculation determines the universal axionic angle that corresponds to the initial condition of our Universe.
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The use of transthoracic echocardiography (TTE) and esophageal Doppler (ED) for the measurement of hemodynamic variables in anesthetized dogs was studied. Fourteen mixed-breed dogs, without cardiac disease, undergoing general anesthesia for diagnostic or therapeutic procedures were included in this prospective preliminary study. Dogs were premedicated with dexmedetomidine (3 µg/kg) and methadone (0.3 mg/kg), intramuscularly. General anesthesia was induced with propofol intravenously titrated to effect and maintained with isoflurane in oxygen. Animals were positioned in dorsal recumbency. Transthoracic echocardiography was performed using a 5-2 MHz cardiac ultrasound probe placed in the subcostal window, whereas esophageal Doppler was performed using a CardioQ probe (MP50; Deltex Medical, Chichester, UK). Once an appropriate view of the aortic flow was obtained, the variables peak velocity (PV) and velocity-time integral (VTI) were measured. Agreement between methods was evaluated using the Bland-Altman method with single observation per individual. The bias and the limits of agreement (LOA) between the two methods were determined. Mean (± SD) PV was 99.46 cm/s (± 42.73 cm/s) and 110.29 cm/s (± 35.86 cm/s), and VTI was 13.24 cm (± 4.33 cm) and 13.05 cm (± 4.47 cm), for TTE and ED, respectively. Mean differences and LOA were 10.83 cm/s (range: -20.50 to 42.16 cm/s) and -0.19 cm (range: -3.32 to 2.95 cm) for PV and VTI, respectively. No statistically significant differences were determined in the variables measured between TTE and ED in anesthetized dogs without cardiac disease, positioned in dorsal recumbency. This could be of clinical relevance when an evaluation of the intraoperative hemodynamic status of anesthetized dogs is desired.
Concordance entre l'échocardiographie transthoracique et le Doppler oesophagien sur les variables du débit aortique chez des chiens anesthésiés ventilés mécaniquement. L'utilisation de l'échocardiographie transthoracique (TTE) et du Doppler oesophagien (ED) pour la mesure des variables hémodynamiques chez les chiens anesthésiés a été étudiée. Quatorze chiens de race mixte, sans maladie cardiaque, subissant une anesthésie générale pour des procédures diagnostiques ou thérapeutiques ont été inclus dans cette étude préliminaire prospective. Les chiens ont reçu une prémédication avec de la dexmédétomidine (3 µg/kg) et de la méthadone (0,3 mg/kg), par voie intramusculaire. L'anesthésie générale a été induite avec du propofol intraveineux titré à effet et maintenue avec de l'isoflurane dans de l'oxygène. Les animaux ont été placés en décubitus dorsal. L'échocardiographie transthoracique a été réalisée à l'aide d'une sonde à ultrasons cardiaque 5-2 MHz placée dans la fenêtre sous-costale, tandis que le Doppler oesophagien a été réalisé à l'aide d'une sonde CardioQ (MP50; Deltex Medical, Chichester, Royaume-Uni). Une fois qu'une vue appropriée de l'aorte était obtenue, les variables vitesse maximale (PV) et intégrale vitesse-temps (VTI) étaient mesurées. La concordance entre les méthodes a été évaluée à l'aide de la méthode de Bland-Altman avec une seule observation par individu. Le biais et les limites d'accord (LOA) entre les deux méthodes ont été déterminés. La PV moyenne (± SD) était de 99,46 cm/s (± 42,73 cm/s) et 110,29 cm/s (± 35,86 cm/s), et la VTI était de 13,24 cm (± 4,33 cm) et 13,05 cm (± 4,47 cm), pour TTE et ED, respectivement. Les différences moyennes et la LOA étaient de 10,83 cm/s (intervalle : −20,50 à 42,16 cm/s) et de −0,19 cm (intervalle : −3,32 à 2,95 cm) pour PV et VTI, respectivement. Aucune différence statistiquement significative n'a été déterminée dans les variables mesurées entre TTE et ED chez des chiens anesthésiés sans maladie cardiaque, positionnés en décubitus dorsal. Cela pourrait être cliniquement pertinent lorsqu'une évaluation de l'état hémodynamique peropératoire des chiens anesthésiés est souhaitée.(Traduit par Dr Serge Messier).
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Doenças do Cão , Cardiopatias , Isoflurano , Animais , Cães , Ecocardiografia , Cardiopatias/veterinária , Isoflurano/farmacologia , Estudos Prospectivos , Respiração Artificial/veterináriaRESUMO
AIMS: Understanding the causes of axonal pathology remains a key goal in the pursuit of new therapies to target disease progression in multiple sclerosis (MS). Anterograde axonal transport of many proteins vital for axonal viability is mediated by the motor protein KIF5A, which has been linked to several neurological diseases. This study aimed to investigate the expression of KIF5A protein and its associated cargoes: amyloid precursor protein (APP) and neurofilament (NF) in post mortem MS and control white matter (WM) and to determine if KIF5A expression is influenced by the presence of MS risk single nucleotide polymorphisms (SNPs) identified in the region of the KIF5A gene. METHODS: Using immunoblotting assays we analysed the expression of KIF5A, APP and NF phospho-isoforms in 23 MS cases and 12 controls. RESULTS: We found a significant reduction in KIF5A and associated cargoes in MS WM and an inverse correlation between KIF5A and APP/NF protein levels. Furthermore, homozygous carriers of MS risk gene SNPs show significantly lower levels of KIF5A protein compared to MS patients with no copies of the risk SNPs. CONCLUSIONS: We conclude that reduced expression of axonal motor KIF5A may have important implications in determining axonal transport deficits and ongoing neurodegeneration in MS.
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Axônios/metabolismo , Cinesinas/genética , Esclerose Múltipla/genética , Esclerose Múltipla/patologia , Substância Branca/patologia , Adulto , Idoso , Axônios/patologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/metabolismo , Proteínas de Neurofilamentos/metabolismo , Polimorfismo de Nucleotídeo Único , Transporte Proteico/genética , Substância Branca/metabolismoRESUMO
Sonic crystals have been demonstrated to be good candidates to substitute for conventional diffusers in order to overcome the need for extremely thick structures when low frequencies have to be scattered, however, their performance is limited to a narrow band. In this work, multiobjective evolutionary algorithms are used to extend the bandwidth to the whole low frequency range. The results show that diffusion can be significantly increased. Several cost functions are considered in the paper, on the one hand to illustrate the flexibility of the optimization and on the other hand to demonstrate the problems associated with the use of certain cost functions. A study of the robustness of the optimized diffusers is also presented, introducing a parameter that can help to choose among the best candidates. Finally, the advantages of the use of multiobjective optimization in comparison with conventional optimizations are discussed.
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Doenças do Gato , Microftalmia , Bloqueio Nervoso , Animais , Gatos , Olho , Microftalmia/veterinária , Bloqueio Nervoso/veterinária , ÓrbitaRESUMO
BACKGROUND: Veterinary medicine has seen significant advancements in locoregional anaesthesia and pain management, including the emergence of the erector spinae plane (ESP) block. However, limited clinical evidence exists on its efficacy and safety. OBJECTIVES: This study compares ultrasound-guided ESP block (ESP group) with an intraoperative intravenous ketamine infusion analgesic protocol (CRI group) in dogs undergoing thoracolumbar mini-hemilaminectomy, focusing on intraoperative opioid consumption, cardiovascular response to surgical stimulation (CR), postoperative pain scores (PS), and postoperative opioid consumption. METHODS: Retrospective, case-control, non-inferiority study conducted in a single centre. Data collected included demographics, bupivacaine dose, ESP block operator, intraoperative recorded variables (haemodynamic variables, CR, complications, rescue analgesia), pre- and postoperative analgesia, 24-hour PS and opioid administration, first food intake post-extubation and postoperative complications. Univariate and multiple regression analyses were applied. RESULTS: One-hundred dogs were included, 75 in the ESP group and 25 in the CRI group. Univariate analysis revealed no significant differences between treatment groups in terms of CR, PS, postoperative rescue analgesia, intraoperative and postoperative opioid consumption, or time to first meal intake. However, the multivariate regression analysis indicated that dogs receiving ketamine infusion had higher CR suspected to be nociception-related (p = 0.036), and higher postoperative opioid consumption (p = 0.013). CONCLUSION: Our study suggests that ultrasound-guided ESP block is as effective as intraoperative ketamine infusion providing perioperative analgesia in dogs undergoing thoracolumbar mini-hemilaminectomy for intervertebral disc disease. ESP group showed significantly lower CR suspected to be nociception-related intraoperatively and lower postoperative opioid consumption within the initial 24 hours.
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The red-giant branch (RGB) in globular clusters is extended to larger brightness if the degenerate helium core loses too much energy in "dark channels." Based on a large set of archival observations, we provide high-precision photometry for the Galactic globular cluster M5 (NGC 5904), allowing for a detailed comparison between the observed tip of the RGB with predictions based on contemporary stellar evolution theory. In particular, we derive 95% confidence limits of g(ae)<4.3×10(-13) on the axion-electron coupling and µ(ν)<4.5×10(-12)µ(B) (Bohr magneton µ(B)=e/2m(e)) on a neutrino dipole moment, based on a detailed analysis of statistical and systematic uncertainties. The cluster distance is the single largest source of uncertainty and can be improved in the future.
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A sound diffuser is proposed based on sonic crystals, structures formed by a periodic distribution of cylindrical scatterers in a host medium, which is usually air. The diffuser is a so-called biperiodic structure, as formed by two arrays of sonic crystals with slightly different periodicities. Large diffusivity at low frequencies is achieved when the typical scale of the blocks is much larger than the periodicity of the crystals, determined by its lattice constant. An interpretation of the low frequency behavior of the diffuser is given in the homogenization limit in terms of multiple reflections and interference between the fields scattered by the different blocks. It is also shown that sonic crystal based diffusers enhance time spreading in comparison with other conventional diffusers.
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PURPOSE: To assess the effect of autologous platelet-rich plasma on the repair of full-thickness articular cartilage lesions in immature rabbits. To that end, the samples were studied using macroscopic, microscopic and biomechanical techniques. METHODS: Twenty-four 11-week-old New Zealand rabbits were divided into two groups based on the treatment (physiological saline serum PCB, autologous platelet-rich plasma PRP). Cartilage lesions were drilled in medial femoral condyle of these rabbits. Other 12 rabbits were under the same conditions, but they did not suffer any lesion and treatment (control group CTR). The three groups were divided into two subgroups, depending on the age at the time of killing (16 and 19 weeks old). RESULTS: The CTR group showed the best possible value in the macroscopic and microscopic evaluation. Meanwhile, the PCB and PRP group values were lower than the CTR group values, at two times of the study, but similar to each other at 19 weeks. In the biomechanical study, at 16 weeks, the CTR and PCB groups behaved similarly, with values above PRP group values, while at 19 weeks, CTR group showed higher values than PCB and PRP groups, and there were no differences between these values. CONCLUSIONS: The evolution of the tissue treated with autologous PRP showed a positive tendency over time, while the PCB group was negative. Nevertheless, at 19 weeks of age, the PRP treatment did not show better results than the PCB, both showing the characteristics of fibrocartilaginous tissue. Likewise, none of the two treatments produced a repair tissue as the healthy cartilage.
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Cartilagem Articular/lesões , Cartilagem Articular/patologia , Plasma Rico em Plaquetas , Animais , Fenômenos Biomecânicos , Transfusão de Sangue Autóloga , Cartilagem Articular/cirurgia , Fêmur/lesões , Fêmur/cirurgia , CoelhosRESUMO
The purpose of this study was to assess the clinical effects of dexmedetomidine, both alone and combined with pethidine or butorphanol, in cats. A prospective randomized blind study was performed. Thirty cats were randomly assigned to three groups of 10 animals: D: dexmedetomidine (20 µg/kg IM); DP: dexmedetomidine (10 µg/kg IM) and pethidine (2.5 mg/kg IM); DB: dexmedetomidine (10 µg/kg IM) and butorphanol (0.4 mg/kg IM). Quality of sedation, analgesia, muscle relaxation and the possibility of performing some clinical procedures were compared using a multifactorial scale. Sedation, analgesia and muscle relaxation increased progressively over time and did not differ in the three protocols. The three protocols facilitated the completion of several clinical procedures. The clinical variables studied showed a similar behaviour in the three protocols and remained close to the baseline, except for a drop in heart rate in protocol D. In conclusion, dexmedetomidine, either alone or combined with pethidine or butorphanol, offers suitable sedation, analgesia and relaxation to perform various clinical procedures in cats.
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Butorfanol/farmacologia , Gatos/fisiologia , Dexmedetomidina/farmacologia , Hipnóticos e Sedativos/farmacologia , Meperidina/farmacologia , Animais , Butorfanol/administração & dosagem , Dexmedetomidina/administração & dosagem , Quimioterapia Combinada , Feminino , Hipnóticos e Sedativos/administração & dosagem , Masculino , Meperidina/administração & dosagemRESUMO
Background: Obesity is produced by the enlargement of the adipose tissue. Functioning as an endocrine organ, it releases and receives information through a complex network of cytokines, hormones, and substrates contributing to a low-chronic inflammation environment. Diet and healthy habits play key roles in the prevention of obesity and its related pathologies. In this regard, there is a need to switch to healthier and more appetizing diets, such as the Mediterranean one. Objective: To compare the mid-and long-term effects of two Mediterranean diet (MedDiet) interventions, one energy-reduced plus physical activity promotion versus a non-restrictive diet, on peripheral satiety-related hormones, weight loss, glucose/lipid metabolism, and pro-inflammatory markers in subjects with obesity/overweight and metabolic syndrome. Materials and methods: A randomized, lifestyle intervention was conducted in 23 Spanish centers, with a large cohort of patients presenting metabolic syndrome. Our study is a subproject set in IMIM (Hospital del Mar Research Institute). Participants were men and women, aged 55-75 and 60-75, respectively, who at baseline met at least three metabolic syndrome components. Subjects were assigned to two intervention groups: (1) an intensive lifestyle intervention with an energy-reduced MedDiet and physical activity promotion (intervention group) with the aim of weight loss; and (2) a normocaloric MedDiet (control). We quantified in a subsample of 300 volunteers from Hospital del Mar Research Institute (Barcelona), following analytes at baseline, 6 months, and 1 year: glucose, HbA1c, triglycerides, total cholesterol, high-density lipoprotein cholesterol, LDL cholesterol, C-peptide, ghrelin, GLP-1, glucagon, insulin, leptin, PAI-1, resistin, and visfatin. Anthropometric and classical cardiovascular risk factors were also determined. A multivariate statistical model was employed to compare the two groups. Linear mixed-effect models were performed to compare changes in risk factors and biomarkers between intervention groups and over time. Results: Compared to participants in the control group, those in intervention one showed greater improvements in weight, waist circumference, insulin (P < 0.001), glucose metabolism-related compounds (P < 0.05), triglyceride-related lipid profile (P < 0.05), leptin, blood pressure, and pro-inflammatory markers such as PAI-1 (P < 0.001) at mid-and/or long-term. High-sensitivity C-reactive protein, resistin, and vifastin also decreased in both groups. Conclusion: A weight loss intervention employing a hypocaloric MedDiet and physical activity promotion has beneficial effects on adiposity, glucose metabolism, lipid profile, leptin, and pro-inflammatory markers, such as PAI-1 in both mid-and long-term.
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AIM: The main aim of this study was to determine the effects of a 10-week plyometric training program on explosive strength, acceleration capacity and kicking speed in young elite soccer players. METHODS: Twenty-two players participated in the study: control group (CG), (N.=11; 18.2 ± 0.9 years) and treatment group (TG) (N.=11; 18.4 ± 1.1 years). Both groups performed technical and tactical training exercises and matches together. However, the CG players followed the regular physical conditioning program, which was replaced by a plyometric program for TG. Plyometric training took place three days a week and included jumps over hurdles, horizontal jumps and lateral jumps over hurdles. Jumping ability, 10 m sprint and kicking speed were measured on five separate occasions. RESULTS: Two-way analysis of variance (ANOVA) with repeated measures reflected that the TG demonstrated significant increases (P<0.05) in jumping ability and acceleration capacity after six weeks of training and in kicking speed with dominant and non-dominant leg after eight and ten weeks respectively. On the other hand there were no significant changes in CG players throughout the study. CONCLUSION: The main findings revealed that a 10-week plyometric program may be an effective training stimulus to improve explosive strength compared to a more conventional physical training program. The improvements in explosive strength can be transferred to acceleration capacity and kicking speed but players need time to transfer these increases.
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Desempenho Atlético/fisiologia , Força Muscular/fisiologia , Educação Física e Treinamento/métodos , Aptidão Física/fisiologia , Futebol/fisiologia , Aceleração , Adolescente , Adulto , Análise de Variância , Índice de Massa Corporal , Humanos , Corrida/fisiologia , Adulto JovemRESUMO
The COVID-19 pandemic has revealed a ventilator deficit in the global health system for this scenario. For this reason, several national and international projects have been developed to get done prototypes of ventilators which could be easy and fast to manufacture. One of the requirements of the AEMPS for conducting clinical studies with new prototypes is through the validation of these new prototypes in an animal model. Therefore, it is important to achieve an animal model which allows us to easily reproduce different clinical scenarios. In this article, we describe the use of a sheep as a research model to assess a prototype ventilator. The animal was anesthetized for 10â¯h in which the prototype was tested in up to 6 different scenarios. This model is effective and easy to reproduce, making it an excellent choice for this kind of research.
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COVID-19 , Síndrome do Desconforto Respiratório , Animais , Humanos , Pandemias , SARS-CoV-2 , Ovinos , Ventiladores MecânicosRESUMO
Cyclosporin A (CsA) is an immunosuppressive drug that inhibits the activity of transcription factors of the nuclear factor of activated T cells (NFAT) family, interfering with the induction of cytokines and other inducible genes required for the immune response. Here we show that CsA inhibits migration of primary endothelial cells and angiogenesis induced by vascular endothelial growth factor (VEGF); this effect appears to be mediated through the inhibition of cyclooxygenase (Cox)-2, the transcription of which is activated by VEGF in primary endothelial cells. Consistent with this, we show that the induction of Cox-2 gene expression by VEGF requires NFAT activation. Most important, the CsA-mediated inhibition of angiogenesis both in vitro and in vivo was comparable to the Cox-2 inhibitor NS-398, and reversed by prostaglandin E(2). Furthermore, the in vivo corneal angiogenesis induced by VEGF, but not by basic fibroblast growth factor, was selectively inhibited in mice treated with CsA systemically. These findings involve NFAT in the regulation of Cox-2 in endothelial cells, point to a role for this transcription factor in angiogenesis, and may provide a novel mechanism underlying the beneficial effects of CsA in angiogenesis-related diseases such as rheumatoid arthritis and psoriasis.
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Ciclosporina/farmacologia , Proteínas de Ligação a DNA/metabolismo , Fatores de Crescimento Endotelial/antagonistas & inibidores , Isoenzimas/metabolismo , Linfocinas/antagonistas & inibidores , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas Nucleares , Prostaglandina-Endoperóxido Sintases/metabolismo , Fatores de Transcrição/metabolismo , Inibidores da Angiogênese/farmacologia , Animais , Inibição de Migração Celular , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Córnea/irrigação sanguínea , Córnea/efeitos dos fármacos , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/farmacologia , Dinoprostona/farmacologia , Fatores de Crescimento Endotelial/metabolismo , Fatores de Crescimento Endotelial/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Linfocinas/metabolismo , Linfocinas/farmacologia , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Mutagênese Sítio-Dirigida , Fatores de Transcrição NFATC , Nitrobenzenos/farmacologia , Regiões Promotoras Genéticas , Prostaglandina-Endoperóxido Sintases/genética , Sulfonamidas/farmacologia , Transfecção , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
The COVID-19 pandemic has revealed a ventilator deficit in the global health system for this scenario. For this reason, several national and international projects have been developed to get done prototypes of ventilators which could be easy and fast to manufacture. One of the requirements of the AEMPS for conducting clinical studies with new prototypes is through the validation of these new prototypes in an animal model. Therefore, it is important to achieve an animal model which allows us to easily reproduce different clinical scenarios. In this article, we describe the use of a sheep as a research model to assess a prototype ventilator. The animal was anesthetized for 10hours in which the prototype was tested in up to 6different scenarios. This model is effective and easy to reproduce, making it an excellent choice for this kind of research.
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BACKGROUND: Rapid sequence induction (RSI) in adults has undergone changes in recent years due to pharmacological and technological advances. The objective of this survey was to evaluate current practice among Spanish anesthesiologists. METHODS: A 31-item questionnaire regarding RSI practice was sent to anesthesiologists working in Spanish public hospitals. Differences in responses according to the type of hospital or experience of the respondent were compared for all data using the chi-square and Fisher's exact test. RESULTS: Approximately 15.89% of Spanish anesthesiologists participated in the survey (1002 questionnaires). The results show considerable heterogeneity in most aspects of RSI. Less than 20% of respondents administer sodium citrate. Sixty-four percent place a nasogastric tube in patients with intestinal obstruction. Gastric residue is assessed by ultrasound in 6% of cases. Only 25% of respondents measure ETO2 to check the effectiveness of preoxygenation, and 22% use nasal oxygen insufflation with nasal prongs or THRIVE. Sixty two percent of respondents apply cricoid pressure, but only 50% release the pressure when encountering intubation difficulty. Up to 40% of respondents reported cases of aspiration despite applying cricoid pressure. Propofol was the most commonly used hypnotic (97.6%), but there was no clear preference in the choice of neuromuscular relaxant (suxamethonium versus rocuronium ratio of approximately 1:1). Only 44% of respondents calculated the dose of sugammadex that would be required for emergency reversal of rocuronium. CONCLUSIONS: The survey showed significant variation in RSI practice, similar to that of other countries. Quality prospective studies are needed to standardize clinical practice.
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Anestesiologia , Padrões de Prática Médica , Indução e Intubação de Sequência Rápida/normas , Pesquisas sobre Atenção à Saúde , Humanos , EspanhaRESUMO
The T cell antigen receptor (TCR) delta gene is located within the TCR alpha locus. A T cell-specific transcriptional enhancer, distinct from the TCR alpha enhancer, has been identified within the J delta 3-C delta intron of the human T cell receptor delta gene. This enhancer activates transcription from the V delta 1 and V delta 3 promoters as well as from heterologous promoters. Enhancer activity has been localized to a 250-bp region that contains multiple binding sites for nuclear proteins. Thus, transcriptional control of the TCR delta and TCR alpha genes is mediated by distinct regulatory elements.
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Elementos Facilitadores Genéticos/genética , Receptores de Antígenos de Linfócitos T/genética , Transcrição Gênica , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Cloranfenicol O-Acetiltransferase/genética , Enzimas de Restrição do DNA , Desoxirribonuclease I , Rearranjo Gênico , Rearranjo Gênico da Cadeia alfa dos Receptores de Antígenos dos Linfócitos T , Humanos , Dados de Sequência Molecular , Mutação , Proteínas Nucleares/metabolismo , Plasmídeos , Regiões Promotoras Genéticas/genética , Sequências Repetitivas de Ácido Nucleico , TransfecçãoRESUMO
The spontaneous formation of dendritic aggregates is observed in a two-dimensional confined layered system consisting of a film composed of liquid crystal, dye and solvent cast above a polymer substrate. The observed aggregates are promoted by phase separation processes induced by dye diffusion and solvent evaporation. The growth properties of the aggregates are studied through the temporal evolution of their topological properties (surface, perimeter, fractal dimension). The fractal dimension of the completely formed structures, when they are coexistent with different types of structures, is consistent with theoretical and experimental values obtained for Diffusion-Limited Aggregates. Under different experimental conditions (temperature and local dye concentration) the structure forms without interactions with other kinds of structures, and its equilibrium fractal dimension is smaller. The fractal dimension is thus not a universal property of the observed structures, but rather depends on the experimental conditions.
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Compostos Azo/química , Corantes/química , Fractais , Cristais Líquidos/química , Microscopia Eletrônica de Varredura , Fatores de TempoRESUMO
AIM: The main aim of the current study was to compare the anthropometrical and fitness profile of female soccer players by level and by playing positions. The second purpose was to explore correlations between kicking speed on the one hand and anthropometric features and explosive strength on the other. METHODS: Female soccer players (N.=190) were tested divided in two groups: elite group (N.=100) and non-elite group (N.=90). Body mass, height, leg length, body composition, counter movement jump, drop jump and kicking speed with both legs were measured. RESULTS: After controlling for experience with multivariate analysis of covariance (MANCOVA), body mass, body fat and muscle mass differed significantly by level. MANCOVA also revealed that all the anthropometrical variables differed by playing position. However, MANCOVA did not show significant differences by level of play, neither for explosive strength nor for kicking speed but revealed significant differences among playing positions. There were significant positive correlations between body mass, height, leg length, muscle mass, counter movement jump height, drop jump height and experience on the one hand and kicking speed with dominant and non-dominant leg on the other for the elite and non-elite players. CONCLUSIONS: Elite players differ from their non-elite counterparts in terms of anthropometrical features, while explosive strength and kicking speed are not sensitive enough to distinguish between levels. On the other hand, the findings indicate few positional variations, and only goalkeepers, tend to have a specific anthropometric and fitness profile. Anthropometric variables, explosive strength and experience have an influence on kicking speed.
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Limiar Anaeróbio/fisiologia , Perna (Membro)/fisiologia , Aptidão Física/fisiologia , Futebol/fisiologia , Aceleração , Tecido Adiposo , Análise de Variância , Antropometria , Composição Corporal , Índice de Massa Corporal , Feminino , Humanos , Atividade Motora , Análise Multivariada , Estatística como Assunto , Adulto JovemRESUMO
Virtual Screening (VS) methods can drastically accelerate global drug discovery processes. Among the most widely used VS approaches, Shape Similarity Methods compare in detail the global shape of a query molecule against a large database of potential drug compounds. Even so, the databases are so enormously large that, in order to save time, the current VS methods are not exhaustive, but they are mainly local optimizers that can easily be entrapped in local optima. It means that they discard promising compounds or yield erroneous signals. In this work, we propose the use of efficient global optimization techniques, as a way to increase the quality of the provided solutions. In particular, we introduce OptiPharm, which is a parameterizable metaheuristic that improves prediction accuracy and offers greater computational performance than WEGA, a Gaussian-based shape similarity method. OptiPharm includes mechanisms to balance between exploration and exploitation to quickly identify regions in the search space with high-quality solutions and avoid wasting time in non-promising areas. OptiPharm is available upon request via email.